1. Field of the Invention
The present invention relates to an electronic component mounting apparatus for automatically mounting an electronic component on a base member of an electronic module such as, for example, a printed circuit board.
2. Prior Art
FIG. 1 shows one example of a conventional electronic component mounting apparatus. The apparatus includes a body 1. The body is provided with a component supply section 12 defined thereon on which a tray is set. A plurality of electronic components are received and arrayed in the tray. The apparatus further includes a mounting head 3 for applying suction to hold one of the components in the tray designated in a program and for carrying it to a place designated in the program. The apparatus further includes a recognition device 4 for recognizing an image of a component held by the head 3 and for judging whether the component is suitable for mounting on a circuit board supported on a support section 5 defined on the body 1. The judgement is carried out by comparing the actual image data of the component obtained by the recognition device 4 with reference data preset for judgement. When the recognition device 4 judges the component to be suitable for mounting, the mounting head 3 carries the component to a designated point on the circuit board on the support section 5 and mounts is thereon. When the recognition device 4 judges the component to be unsuitable for mounting, the head 3 carries the component to a disposal section 7 defined on the body 1 and releases its hold on the component to allow the component to fall into the disposal section 7. Shown at 6 and 8 are a controller and an operation board, respectively.
The conventional apparatus suffers from the following problems.
In the conventional apparatus, when any component is judged to be unsuitable for mounting, it is dropped into the disposal section. When dropped, the component may be deformed upon impact, thereby resulting in a situation wherein it is impossible to judge which part of the component was originally defective, how great such a defect was and so on, namely, the condition of the component when the component is judged to be unsuitable for mounting.
Sometimes the image data obtained by the recognition device 4 may be so poor that the device 4 is not able to recognize the image of the component correctly. At other times, a component may be extremely mis-positioned with respect to the head 3 when it is held by the head 3 so that the recognition device is also unable to recognize the image of the component correctly. In those cases, the recognition device 4 judges the component to be unsuitable for mounting. The recognition device 4 may, therefore, perform a misjudgement, and judge a good component to be unsuitable for mounting and dispose of it. When disposed of, such a component may be damaged, thereby making re-use of the component impossible.
In the conventional apparatus, the success rate of mounting is obtained as production managing information. In this connection, it is noted that there are two reasons for electronic components being judged unsuitable for mounting. One is when the mounting head 3 fails to hold a component in the condition predetermined in the program so that the head fails to hold the component, or so that the component is mis-positioned with respect to the head. The other is when leads of the component are damaged by being bent or the shape of the component itself is distorted. In the conventional electronic component mounting apparatus, the production managing information cannot be sorted according to respective causes of unsuitability.